D-sub our of range on second monitor

Installing a second monitor using an ATi Radeon 9550 card. Monitors are NEC LCD 1830 as primary, secondary is LCD 1570NX. Connected with analog splitter.

All of the latest drivers, including the Intel chipset driver for my Dell Dimension 8200.

I get only a duplicate of my primary desktop. Second monitor shows in ATi and Windows properties; resolution shows properly for both. However, when I try to activate the second display and extend my desktop, just get a "D-Sub Out of Range" error message on the secondary monitor. Cables?

If you are splitting the output from one of the graphic card's connectors, you can only expect what you are getting. The second monitor has to be connected to the second connector on your graphics card.

Well folks, thanks for the reply, but I have done this on about half-dozen systems at my office - all work just fine. In addition when the system boots each monitor displays its individual resolution screen, indicating that it is identifying each. Finally, the card help files also indicate support for extended desktop over more than two screens, and there is no additional connection (other than the DVI, which you cannot plug into at the same time as the analog). I believe that it has to do with either a system driver or an device driver, but not sure.